Effects of the combined use of linaclotide and oral sulfate solution in bowel preparation for patients with chronic constipation undergoing colonoscopy: protocol of a prospective, randomised, controlled, single-blind clinical trial from a single centre in China.

INTRODUCTION

Chronic constipation is an independent risk factor for inadequate bowel preparation. The objective of this study is to evaluate the effectiveness and safety of the combined use of linaclotide and oral sulfate solution (OSS) in patients with chronic constipation undergoing colonoscopy.

METHODS AND ANALYSIS

This is a prospective, randomised, controlled, single-blind (endoscopist) clinical trial that compares three bowel cleansing regimens for patients with chronic constipation undergoing colonoscopy. Regimen A consists of 2d-linaclotide and OSS, regimen B consists of 3d-linaclotide and OSS, and regimen C consists of OSS. All patients are required to consume a low-fibre diet for 3 days and then a clear fluid diet for 1 day before the colonoscopy. The primary outcome is adequate bowel preparation (defined as a Boston Bowel Preparation Scale (BBPS) score ≥2 for each segment and a total BBPS score ≥6). The secondary outcomes include defecation frequency, caecal intubation rate, adenoma detection rate and colonoscope insertion time and withdrawal time. The tertiary outcomes include complications of colonoscopy, adverse events and degree of comfort, which is evaluated via a self-designed questionnaire of comfort.

ETHICS AND DISSEMINATION

The research will be conducted according to Good Clinical Practice principles. Ethical approval has been obtained from the Ethics Committee of Beijing Shijitan Hospital, Capital Medical University (IIT2024-146-003). Study findings will be published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

ChiCTR2500096394.

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